Serena Williams of the United States returns to Caroline Garcia of France during their Women's second round singles match at the All England Lawn Tennis Championships in Wimbledon, London, Thursday, June 27, 2013. (AP Photo/Alastair Grant)

Serena Williams of the United States serves to Caroline Garcia of France during their Women's second round singles match at the All England Lawn Tennis Championships in Wimbledon, London, Thursday, June 27, 2013. (AP Photo/Alastair Grant)

Kimiko Date-Krumm of Japan returns to Alexandra Cadantu of Romania during their Women's second round singles match at the All England Lawn Tennis Championships in Wimbledon, London, Thursday, June 27, 2013. (AP Photo/Anja Niedringhaus)